1. Field of the Invention
Apparatuses consistent with the present invention relate to a non-invasive measurement of body components and, more particularly, to a system for non-invasively measuring body components using Raman spectroscopy and a non-invasive probe included in the system.
2. Description of the Related Art
As the quality and environment of life have been greatly improved, peoples' interest in individual health has increased. Thus, research for developing household medical instruments, by which a person's state of health can be easily checked, has been performed, and a lot of new products are being developed. In the body of a normal person, bio-fluids exist, which are organically circulated and controlled to be maintained within a predetermined range. The bio-fluids can include blood, urine, interstitial fluid, and sweat. Concentrations of bio-fluid components such as glucose, hemoglobin, bilirubin, cholesterol, albumin, creatinine, protein, and urea included in the bio-fluid are among the variables which represent the state of a person's health, and thus are among the subjects to be measured.
If a person suffers from an illness, the composition or quantity of the bio-fluid components changes, and that person can be in danger. For example, the concentration of blood glucose of a normal person is about 80 mg/dl before a meal, and about 120 mg/dl after a meal. The human body makes the pancreas produce an appropriate amount of insulin before or after the meal and the liver and skeletal muscle cells absorb the insulin in order to maintain the above concentration of the blood glucose.
However, if the appropriate amount of insulin required to maintain the normal blood glucose cannot be produced by the pancreas due to an illness or other cause, an excessive amount of glucose will exist in the blood, which may cause heart disease, liver disease, arteriosclerosis, hypertension, cataract, retinal hemorrhage, nerve damage, loss of hearing ability, amblyopia, or even worse, the person's death. Therefore, it is very important to diagnose a person's state of health by measuring the concentrations of the bio-fluid components before any illnesses result.
The concentration of the bio-fluid components, in particular, the blood glucose included in blood, can be measured by using an invasive method, which measures the concentration of a certain bio-fluid component by directly collecting blood. Alternatively, a non-invasive method, which measures the concentration of the bio-fluid component without collecting the blood can be used. While the invasive method can obtain highly reliable measurements, it also has several disadvantages including the pain caused by the blood collection using a syringe, possible infection and inconvenience. In addition, direct blood collection imposes an economic burden on a user due to the need for supplies such as a strip for measuring the bio-fluid component and the syringe.
Non-Invasive Technique for measuring the bio-fluid components, such as the blood glucose, using Raman spectroscopy are well known. According to these Techniques a ray of light having a certain wavelength is focused and irradiated onto a certain portion of the body, a capillary vessel for example, and the concentration of blood glucose is measured using a Raman spectrum, the wavelength of which is changed by glucose molecules.
According to the measuring method using Raman spectroscopy, the magnitude of signals in a Raman spectrum, which is obtained by irradiating the light, is small. To solve this problem, the intensity of the light incident into the human body can be increased; However, the increased intensity of light may cause a burn. Alternatively, the concentration of blood glucose can be measured using a plurality of Raman spectrum signals obtained by irradiating the light multiple times; however, it may take three minutes or longer to measure the concentration of the blood glucose using multiple irradiations of light.